WonkoTheSane

iTrader: (2)

Status: trying to get my rebuild started.

After a long, vicious battle with fuel injectors and grounds, i feel i have finally won out. (See thread: https://www.rx7club.com//showthread....hreadid=299849 , if you care).. Now i know I have fuel in the engine, so i pulled my spark plugs to check and make sure i have spark from all my coils. What's happening is that every coil (well, 3 out of 4, one is dead), when the spark plug is held near a ground, will spark once (immediatly after you start cranking), and then never again.. we've left it cranking for up to 20 seconds, and the plug will never fire again, until you stop cranking and then start again.. it does this for all 3 functional coils..

I just noticed that i haven't connected any of the packs in front of the radiator yet, (I haven't put the lights back in or anything), do they control anything to do with the timing or spark?

any help?

thanks!
~Wonko The Sane

WonkoTheSane

iTrader: (2)

bueller?

rotoboy20

something isnt connected, ive run into that problem befor. make sure you plug everything up, it should run.

HAILERS

Try this. Lay all four of your plug wires on near the strut tower.

Take the cas out of it's bore but leave the harness connected.

Turn the key to ON.

Now spin the cas's gear over rapidly and tell me you did/did not see all four of the spark plug leads arcing.

And by now you know or knew that you only have three coils. The Lead coil assy has but one coil and one ignitor. Both wires on that coil have to be connected to a sparkplug or touching ground for one or the other to spark.

The coil assy must be bolted to the chassis for the ignitors to work. Just one bolt will do the job. But if you lay the coil assy on a rag or piece of wood the ignitor will not fire.

On an american car the fuel line from the fuel filter goes to the forward pipe on the engine.

WonkoTheSane

iTrader: (2)

Status report:

I've followed your instructions Hailers. I've taken out all four plugs, and grounded them. Here's what i've observed. If i take the CAS out, and spin it, i will get nothing through any of them. If I crank the engine, three out of four will fire simultainously right a the beginning, and never again (until the next crank).. any idea what it means? I know both coils are ground rather well, as i just took them off and sanded underneath. I've checked the connection between the CAS and the ECU, and i'm getting good continuity to both sides.

Awaiting instructions, please.

WAYNE88N/A

well, what the heck, somebody else had the funky thing going with the AFM being bad and not getting spark, maybe there's something in the air...AFM plug on? the capacitor under the trailing coil pack connected to ground? main relay contact dirty (the contacts for the ignition circuit, anyway?) coil terminals connected properly from the harness? good ground on the upper rear rotor housing & below the trailing coil pack?

WonkoTheSane

iTrader: (2)

i'll go double check the AFM now... I did double check the ground for the little cap, and I just rebuild the main relay with two brand spankin' new relays, so i'm pretty sure that's good (besides, that one is easy, they both click on) any way to trick the AFM to bypass it in case that is it?

HAILERS

The trigger for the LEAD coil assy comes from the pin 1V on the ECU to the small white plug on the Lead coil assy. There are two wires there. One is black/yellow with a constant 12v with the key to ON and the other wire is *from memory* a green/yellow wire *I think*. Anyway it goes to pin 1V on the largest plug on the ECU. Check continuity there since you already checked out the wiring b/t the cas and the ECU.

Yeah that is odd....just one spark. I really don't think afm's have squat to do with spark at all.

I do know that if I take the wires off the plugs and lay them anywhere near a ground that they will spark a plenty when I twirl the cas.

Also go to your boost sensor, pull the plug off and put a meter on the brown/red wire with the key to On. You should see approx 4.5 volts. What do you have on your car????

If you get a chance, pull the middle plug off the ECU. Put the meter on ohms and the neg lead on a good ground. Then put the pos lead on the pin 2R. You should have a good ground showing on the meter. Like .2 to .6 ohms or there abouts. Just fishing.

I think you know how to count wires on the ECU plugs. You look at the end where the wires enter th plug. 1A will be on the top row, far right. 1B will be just below it, bottom row, far right. And you count like that from right to left til you come across the pin your looking for.

Plug 1 is the large one to the right. Plug 2 is in the middle and plug three is the small one to the far left on the ECU.

Just one spark. Hurumph.

WonkoTheSane

iTrader: (2)

okay, i'm checking out the AFM, all tests come back well within spec except for one.. . according to FSM, when E1 and FC's resistance is read, there should be zero resistance when fully open.. mine stays @ no reading through the entire range.. this is supposed to be the fuel pump switch, is this affecting anything?

HAILERS

By the way, twirling the cas saves the starter, that's why I suggest this method if you have a clue on how to install a cas, and you do.

WonkoTheSane

iTrader: (2)

okie, i'm going to check those things now, Hailers.. I figured that doing the CAS manually would allow me to see (sequentially) if the plugs are firing... but they're not, except for that initial zap... good idea about saving the starter, though


maybe when i finally get this running, i'll be able to actually help other people

WAYNE88N/A

You could jumper the fuel pump check connector if the AFM door switch is bad to keep the fuel coming, but here we go again- how the hell is that AFM cutting ignition? (in case that's it)...anybody got the internal schematics for the ECU?...Hailers?

HAILERS

The afm has squat to do with spark. Go out to your car and pull the afm's plug. Then pull your cas. Then turn the key to ON. Then spin your cas with the plug wires laying loosly on/near the strut tower. Spark, spark, spark, spark, spark all day long.

If you don't get spark, let me know.

WonkoTheSane

iTrader: (2)

I don't get spark... but I think we were trying to figure out why, there...

I went through everything you said, Hailers.. everything appears to be working exactly like you described, except for the boost sensor, i couldn't get any of them to register any voltage at all???

Bloody cars.. everything else appears to be good, and we even went and checked all of the trailing wires to the ECU... the only one that confused me there was the Yellow/Blue wire, it looks like it's dependant on the clutch switch, so I shorted the clutch switch just to be sure (the switch was closed (proper position to start the car)), and i still can't get anything other than some resistance through it..

this really has me stumped.

WAYNE88N/A

HAILERS, if I had to guess one way or the other, I'd have to agree with you (that the AFM has "squat to do with spark")...But I've heard, what, 2 or 3 guys now that said they had a spark prob, and fixed it with an AFM...that's why I need to see the ECU internal schematics, so I can settle this for myself once and for all...I mean you got what, 2 pins for the door switch, 1 pin for 5v ref, 1 pin for the 3v or so output from the pot, 2 pins for the ground through the ECU, and 1 pin for the intake air sensor output...WTF? could the ground through the ECU have anything to do with it (ignition)? Little off topic here, I know, but this is driving me batsh#t,

WAYNE88N/A

Wonko- check your TPS 5v ref voltage (Br/W)(86-88)...do you get it there?

HAILERS

[QUOTE]Originally posted by WonkoTheSane
[B]I don't get spark... but I think we were trying to figure out why, there...

I went through everything you said, Hailers.. everything appears to be working exactly like you described, except for the boost sensor, i couldn't get any of them to register any voltage at all???

Oh, good. Now we're getting somewhere. IF you read the meter right and this is a series four car.

About the boost/pressure sensor. With the key to ON (not start), you should have 4.5 volts on the brown/red wire at the boost sensor connector. Also you should have had 12v on the black/white wire. So tell you what, let's have you try that again...voltage on the black/white wire and on the brown/red wire. You sure you don't have 12v on the black/white wire and 4.5 volts on the brown/red?

The lack of 4.5 volts tells me there is no Reference voltage being put out by the ECU which in turn (in my mind) that you won't get spark because you won't have a approx 5v trigger being put on the pin 1V to the Lead COIL assy.

The 12v on the black/white wire at the boost sensor comes from the Main Relay. It should be there if you have the key to ON. It should also exist at each solenoid on the rack. Each of those plugs has a black/white wire. Each one should have 12v on their black/white wire.

So check a couple of black/white wires at the solenoids while your poking around. No 12v???? Then we can start over again.

HAILERS

Forget about the afm. It has squat to do with spark. Like I said. Pull the afm plug off. Pull your cas but leave the harness on. Put the sparkplug wires on the chassis somewhere. Key to ON. Spin the cas. Spark all day long as long as you rotate the cas.

The car in this post seems to be lacking any output from pin 1V to make the ignitor spark.

It's been noticed in the past, that if there is no reference voltage output from the ECU, that that has a relationship to whether or not the ECU can put out voltage on pin 1V for the ignitors to spark.

WonkoTheSane

iTrader: (2)

cool Hailers, it seems like you understand what's going on unfortunatly, i'm going to have to wait until t/w to check it out. after I get out of school, i'll post here and let you know what happens

WonkoTheSane

iTrader: (2)

I Would like to start out by saying this. I, Wonko T. Sane, am a Dumbass.. Thanks to everyone who helped me troubleshoot over the past two weeks. Hailers, i want to personally apologize to you, for wasting your time... the #$*@@#$!ing fuse was blown.. for the EGI... it was a hairline fracture, and the only reason i noticed it was because i was looking at schematics right above it while tracing out your suggestions.. i feel like an idiot...

that said... it still hasn't started, but i figured it's just a matter of cranking the hell out of it/oiling it.. I now know i have consistant spark on ALL 4 coils, and i'm getting fuel into the engine... damn i feel stupid...

any suggestions for building compression? (I'm assuming that's why it's not starting now)....

WAYNE88N/A

injecting a little eng oil into the plug holes (1 each rotor) always works for me...

WonkoTheSane

iTrader: (2)

it is SOOOOOOOOOOOOOOO close to turning over... i don't know why it's not turning over, but it's spinning so fast and sounds really close... man, this is tense

WAYNE88N/A

S4? hold the peddle to the floor till she catches, then keep her going at a high idle for a while...

WonkoTheSane

iTrader: (2)

cool, i'll try that tomorrow thanks!